In a conventional electronic flash, the primary capacitor charge detection and display means is not associated in operation with the trigger circuit of the flash discharge tube. Therefore, the conventional electronic flash is disadvantageous in that if the trigger circuit is operated before an indication is given that the main charge storage capacitor is adequately charged, the intensity of light emitted is inadequate. That is, a voltage may be supplied to trigger the trigger circuit before the fact that the main capacitor has been charged is detected and displayed. It is impossible for a single circuit to provide a voltage level for controlling the operation of the trigger circuit at the time of display of the charge completion because of fluctuations in circuit element parameters.
An electronic flash may be not operated merely by opening the power switch to stop the operation of the DC-DC converter. That is, if the power switch is opened, the main capacitor is still maintained charged and the trigger circuit is also maintained energized. If, under this condition, the X contact is closed, the electronic flash will be actuated so that the flash can thus be operated unintentionally.
Accordingly, an object of the invention is to eliminate the above-described difficulties accompanying a conventional electronic flash. Another object of the invention is to provide a charge detection display type electronic flash in which the fact that the main capacitor is charged is detected to positively operate a camera control circuit.